Bid to save Thai coastline

2009-10-06 17:07

Bang Khun Thien - Some villagers use bamboo fencing. Others plant mangroves. And some do both to fight back against erosion transforming centuries-old communities on the Gulf of Thailand.

Only a half hour drive south of Bangkok, coastal regions already show alarming signs of erosion: electricity poles, once on land, are submerged in parts of Bang Khun Thien, a district on the outskirts of Bangkok.

Kongsak Lerkngam, who lives in Bang Khun Thien and works on an erosion protection initiative in six coastal provinces, said about 460 hectares of village land have disappeared in the past 30 years at a rate of between 1.2-4.6 metres a year.

Caused by a combination of expanding fishing industries such as shrimp farms and global warming that has raised sea levels, the erosion has wiped out many of the mangrove forests that once offered a natural buffer on the Gulf of Thailand coast.

"The forest is gone," Kongsak said of the mangroves.

"In the past, erosion was not this intense but now the erosion is very intense," he added.

Most of the affected regions were cleared of mangroves by shrimp farms, a big business in Thailand that brings in $2bn in exports a year.

Some villagers are fighting back with varying degrees of success. In 1999, about 46 villages began planting mangroves in an attempt to revive the ecosystem of trees and shrubs which once formed a coastal barrier to protect their communities.

Their goal: stop the ripples caused mostly by fishing boats from reaching the water's edge where many homes are built.

Harnessing bamboo

Other villages take a different approach.

In Kok Kham, a fishing community in the province of Samut Sakhon, some villagers have built bamboo fences by submerging about 100 bamboo sticks, each about 5 metres long, in triangle-shaped groups along the coast.

The idea is to prevent big ripples from reaching the coast and allow mud and debris to collect on the fence to form a barrier, said Narin Boonruam, a 71-year-old leader of the Kok Kham Conservation group. "This helps relieve coastal erosion."

But the bamboo fences protect just two km of Samut Sakhon's 42km of coast.

Still, Narin said he is satisfied with the result. Sediment behind the fences has swelled to 1.5 metres thick in just two years. Mangrove trees have also been planted but are too thin to withstand strong ripples and protect the coast, he added.

The International Union for Conservation of Nature (IUCN), a network of campaign groups, governments, scientists and other experts, described the local techniques as a good answer to a troubling problem in Thailand.

"It works. It's natural. It's sustainable," said Thailand IUCN Programme coordinator, Dr Janaka De Silva.

"It has added benefits in that it improves the quality of local peoples' livelihood."

His comments come as scientists and government officials from around the globe meet at a UN conference in Bangkok to work out ways to fight climate change and curb the growth of greenhouse gas emissions.

According to a 2007 World Bank report, about 1 500km² of Gulf of Thailand mangrove forest has been deforested and replaced by shrimp farms.

It estimates 11% of Gulf of Thailand coast has been eroded at a pace of five metres or more a year.

- Reuters